Fluid switching device

ABSTRACT

A device comprising a first nozzle having an interior chamber, a pair of inlet passages communicating with the chamber through tangential portions thereof, and a recovery nozzle, the form of the jet issuing from the first nozzle being dependent upon the pressures of the inlets and only when they are equal is there a laminar stream issuing for reception in the recovery nozzle.

United States Patent 2 Inventor Robert Thomas John Skinner I 3,272,2139/1966 Jones 137/815 Kenilworth, England 3,272,215 9/1966 Bjornsen eta137/815 21 Appl, No. 727,581- 3,285,263 11/1966 Bjornsen m1 l37/8l.5[22] Filed May 8,1968 3,413,995 12/1968 Bowles et al l37/81.5 [45]Patented Jan. 12, 1971 v 3,426,534 2/1969 Murphy 137/81.5X [73]'Asslgnee Joseqh L gndustsles) Limited Primary ExaminerSamuel ScottBirmmg Attorney-Holman & Stern [54] FLUID SWITCHING DEVICE 2 Claims, 5Drawing Figs. I 52 u.s.c1.... 137/815 ABSTRACT: A device comprising afirst nozzle having an i 1 llll- C| Flsc 16 terior chamber, a pair ofinlet passages communicating with [50] Field of Search the chamberthrough tangential portions thereof, and a recovery nozzle, the form ofthe jet issuing from the first noz- 1 References c'ted zle beingdependent upon the pressures of the inlets and only UNITED STATES PATE Twhen they are equal is there a laminar stream issuing for 3,256,8996/1966 Dexter et a1. 137/8l.5 reception in the recovery nozzle.

PATENTEU JAN I 2m INVEN'TO R Shh/wt B 4M, ATTORNEYS FLUID SWITCHINGDEVICE the first nozzle having an interior chamber, tangentiallyarranged passages disposed in-at least one oppositely directed pairalong which streams of fluid flow from the two sources of fluidsentering the chamber from the two sources along the oppositely arrangedpassages are equal, any tendency for rotation of the fluid about theaxisv of the; chamber will be prevented thus causing fluid to be emittedin a lamina stream of a form to be received by the. recovery noule, andif the pressures are unequal, there will be rotation within the chamberresulting in the emission of the fluid as a substantially hollow conewhich will affect the reception at the recovery nozzle.

The invention will now be described. by way of example with reference tothe accompanying drawings in which:

FIG. 1 is a cross-sectional view of a device constructed in accordancewith the invention; and I V FIG. 2 is a cross-sectional view on the line2-2 in FIG. 1;

FIG. 3 is a diagrammatic representation of an alternative form of thedevice on a reduced scale; v

a FIG. 4 is a cross-sectional view on a reduced scale of a furtheralternative arrangement; and

FIG. 5 is a cross-sectional viewofa further form of the first nozzle inFIG. 1. a ,1

With reference to FIGS. 1 and .2 there is provided a first nozzle havingan outlet 11 arranged in alignment with an entry opening 12 of arecovery nozzle 13- The nozzles 10 and 13 are disposed in a body 9 whichis. provided with a drain passage 14. The recovery nozzle 13 is -asimple nozzle with a coaxial outlet passage 13a. 1

The first nozzle 10 has a pair of inlets 15, 16, the former beingannular and surrounding the latter. There is, in the interior of thefirst nozzle 10, a chamber 17 which in this example has a frustoconicalmidregion, the wider end being formed as a cylindrical portion and thenarrower end being formed by the cylindrical outlet 11. The inlets 15,1.6 communicate with the interior of the chamber 17 at the wider endthrough two pairs of passages 18, 19. The terminal regions of thesepassages 18, 19 adjacent to the chamber 17 are formed tangentially withrespect to the cylindrical portion of the chamber 17, each passage 18being arranged in opposition to an associated passage 19 as illustratedin FIG. 2.

The arrangement is such that if fluid is supplied to both inlets 15, 16of the first nozzle 10 simultaneously there will be created in thechamber 17 a flow which will be'emitted as a stream through the outlet11 in the direction of the recovery nozzle 13. If the pressures in theinlets l5, 16 are equal, there will be no tendency for the fluid inthechamber 17 to rotate about the axis of the nozzle 10, and accordingly,the emitted stream will be substantially cylindrical and lamina and asubstantial proportion ofthis will therefore be received in the recoverynozzle 13. If, however, the pressures in the inlets I5, 16 are unequal,there will be a tendency for the fluid to rotate inside the chamber 17,and it will thus be emitted as a substantially hollow cone of an anglesuch that there will be no appreciable recovery of the fluid in thenozzle 13. These alternative flow patterns are illustrated in FIG. 1.

In an alternative arrangement, there are only two passages I8, 19disposed as one pair of opposed tangentially arranged passages. I

With reference to the construction illustrated in FIG. 3.

there are provided two nozzles 20, each of the kind identified bynumeral 10in FIG. 1, having respective outlets 21 disposed lustrated)and the arrangement is such that flow can take place either from rightor left, or from left to right as illustrated in the drawings, andcontrol can be achieved in whichever direction is chosen.

In the example illustrated in FIG. 4, there is provided a nozzle 23having an outlet 24 and a generally frustoconical chamber 25, similar tothe chamber 17 of the FIG. I construc tion, but there are three separateinlets 26, 27 and 28, the former two being annular and surrounding thelatter.

The inlets 26, 27 communicate through passages 29, 30

. with the chamber 25 through tangential passages as illustrated inFIGS. 1 and 2, but additionally, a continuous supply of fluid reachesthe chamber 25 through the inlet 28.

In use, if only the inlet 28 is supplied with fluid, there will beemitted a substantially cylindrical and laminastrearn of fluid which canbe received in a recovery nozzle (not illustrated), but if either of theinlets 26 or 27 is also supplied with fluid, the flow pattern will bedisturbed and conical flow will take place so that recovery in arecovery nozzle is substantially prevented. Such conical flow patternwill be produced if only one of the inlets 26 or 27 is in use, oralternatively, if both are in use with the pressures therein unequal.Conditions for recovery in a recovery nozzle will, however be achievedwhen both the inlets 26 and 27 are being supplied at equal pressures.

In the FIG. 5 construction the nozzle 31 shown is to replace the firstnozzle 10 of FIG. 1 and differs from it only in that the chamber 32within it has a stepped cylindrical outlet of which the separatecylindrical portions are identified by numerals 33 and 34 respectively.The larger diameter portion 34 is nearer to the frustoconical portionand is of equal diameter to the smaller end thereof.

With nozzles of the kind described accurate control of the outlet fromthe first nozzle can be achieved and, for example, if the averagepressures in the nozzle are in the region of 1,000 pounds per squareinch, a change in only l5 pounds per square inch suffices to change theflow pattern to affect control The degree of change in flow patternbetween the two extremes, is however, dependent upon the relativepressures, in this small pressure range.

The recovery nozzle may be connected in a passage in which a fluid flowor pressure signal is required in accordance with the inlet pressures.

The devices may be used with either liquids or gases.

I claim:

1. A device comprising a first nozzle to which fluid can be suppliedunder pressure simultaneously from two independent sources, and arecovery nozzle aligned with said first nozzle, the first nozzle havinga coaxial interior chamber, passages communicating with the chamber,tangentially thereof, said passages being arranged in two oppositelydirected pairs, one of each pair being connected to the two sourcesrespectively, the recovery nozzle being arranged to receive fluidemitted from the first nozzle when such fluid is emitted in a laminarstream, when the pressures of fluid in the two pairs of passages areequal, and the recovery nozzle being arranged to receive a smallerproportion of the flow when theemission is in the form of asubstantially hollow cone, when the pressure of fluid in the two pairsof passages are unequal.

2. A device as claimed in claim 11 inwhich the recovery nozzle is thesame as the first nonle and'has an interior chamber and passagesarranged to communicate with sources respectively, a

1. A device comprising a first nozzle to which fluid can be suppliedunder pressure simultaneously from two independent sources, and arecovery nozzle aligned with said first nozzle, the first nozzle havinga coaxial interior chamber, passages communicating with the chamber,tangentially thereof, said passages being arranged in two oppositelydirected pairs, one of each pair being connected to the Two sourcesrespectively, the recovery nozzle being arranged to receive fluidemitted from the first nozzle when such fluid is emitted in a laminarstream, when the pressures of fluid in the two pairs of passages areequal, and the recovery nozzle being arranged to receive a smallerproportion of the flow when the emission is in the form of asubstantially hollow cone, when the pressure of fluid in the two pairsof passages are unequal.
 2. A device as claimed in claim 1 in which therecovery nozzle is the same as the first nozzle and has an interiorchamber and passages arranged to communicate with sources respectively.